<!DOCTYPE html>
<html class="reftest-wait">
<head>
<style type="text/css">
#separator {
 height: 20px;
 background-color: green;
}
#float {
 float: left;
 width: 50px;
 margin: 20px 0;
 background-color: green;
}
#child {
 height: 20px;
 background-color: lightgreen;
}
</style>
<script type="text/javascript">
function test() {
 document.getElementById('child').style.margin = '40px 0';
 document.documentElement.removeAttribute('class');
}
document.addEventListener('MozReftestInvalidate', test, false);
</script>
</head>
<body>
<div id="separator"></div>
<div id="float">
 <div id="child"></div>
</div>
</body>
</html>
